After the firing a firearm, be it pistol or rifle, cleaning is required to remove gunpowder residue from the barrel. To clean the barrel—jag, patch, brush and rod are primarily used.
A firearm barrel has a loading breech at one end and a discharge muzzle at the other end. Grooves or rifling are cut into its bore. A barrel cleaning operation starts with the threaded attachment of a caliber-specific jag to a rod. A small square or round cotton patch, typically saturated with a cleaning solvent, is placed over the end of the jag and inserted into and down the barrel. Insertion of the rod with the attached jag is preferred at the breech end, as the muzzle end has a crown that could be damaged and possibly affect accuracy. Jag and patch are pushed down the barrel, moistening the internal surfaces with the cleaning fluid contained in the patch.
Barrels are drilled and that longitudinal hole is the bore. Rifling consists of cutting spiraling grooves into the bore's interior surfaces. Barrels can contain 2-20 grooves. Separating the grooves are lands. Grooves are cut 2 to 6 thousandths of an inch deep (0.05 to 0.15 mm) with a specific twist or spiral down the length of the barrel's bore. Twist can vary from 1 revolution every 66 inches to 7 inches (168 to 18 cm).
The purpose of the grooves and lands with twist is to capture and spin the bullet. A spinning bullet has directional gyroscopic inertia for accuracy.
After firing, a barrel contains spent gunpowder residue consisting of ash, carbon and metallic particles. Firing a copper-lead bullet down a barrel with the ignition of black or smokeless propellant powder is done under high temperature and pressure conditions. The resultant residue is hard, charred, abrasive, adherent, corrosive and scaly.
Present removal technique involves initial whetting of the barrel bore's grooves and lands with a liquid substance via the jag with patch or swab described above. The liquid substance is passed over the surfaces of the grooves and lands to soak and loosen the residue. Concurrently, a bore brush, attached to a rod, is passed down the barrel. The effect of the brush is to loosen the scaly residue from the surfaces of the grooves and lands.
Removal of the loose residue is accomplished by the passing of a jag with patch down the barrel. The patch collects the residue. Collection is aided by the interstitial spaces between the jag's ribs that provide pockets to collect captured residue. Successive clean patches are run down the barrel until no residue can be found on the passed-through patch.
Since the residue is loosened in moistened layers, additional procedures of liquid soaking, brushing and dry patching is required to fully clean the barrel's grooves and lands.
However, this present method of cleaning is ineffective and detrimental. Brushes, made of brass and hard plastic ride down the bore, crossing diagonally over the twisting lands, not contacting all of the surfaces of the grooves and lands.
The jag has remained virtually unchanged for about 150 years. It is sized significantly smaller than the bore. Even if wrapped in a cotton patch, it cannot reach the larger diameter grooves. Instead, it relies on the bunching of excess patch or skirt to gently wipe the groove surfaces. This design fails to allow for application of controllable and uniform pressure.
In one prior art example, Chief's Pro Clean (Powhatan, Va.) U.S. Pat. No. 6,691,441 B2 markets a bore cleaning product for muzzle-loading rifles. The commercial form of this product is advertised as a tool that removes and collects the residue left in the rifling grooves. Its polymer tracker feature follows the land walls of the rifling, while a thin brass scraper reaches into the grooves to remove caked-in residue. This product may be effective for muzzleloaders that use black powder (BP) or synthetic BP, but is not suitable for use with smokeless powder type firearms. In particular, residue left by black powder contains larger particles and more content than residue left by high-power rifles using smokeless powder. However, smokeless gunpowder residue is much finer, and cannot be effectively removed by this product. Furthermore, this product is essentially a scraper capable of working only in one direction. Its thin brass scraper and nylon holders have the potential to bind inside the bore, thus scratching the lands and the grooves within the bore, and cannot fully clean the inner bore surfaces. For this reason, this product requires the use of a loose-piece bushing that acts as a guiding tool seated over the muzzle end. This tool's nylon material will wear out quickly under heavy use. Prior to use of this tool, a traditional jag must first wet the bore with an oiled patch. Also, the relatively loose-fitting nature of this tool inside a bore is not well-suited to indicating problematic areas along the length of a bore that require a deeper cleaning. The tool also relies on a traditional jag with patch to follow after cleaning in order to absorb and remove loosened residue.
Accordingly, no known prior art, including the Retriever, is suitable for use in firearms that use gunpowder to thoroughly and rapidly clean, scrub or polish the bore without damaging its rifling.
Thus, there exists a need for an improved reciprocating firearm barrel cleaner for use with gunpowder firearms that more thoroughly and rapidly cleans, scrubs, and polishes a firearm barrel without damaging its rifling.